ArticleClinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases2020
Detection of SARS-CoV-2 N-antigen in blood during acute COVID-19 provides a sensitive new marker and new testing alternatives.
Article in Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Cited by 42 papers, 2 of them syntheses that pooled it.
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Who cites it
42 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Rapid, point-of-care antigen tests for diagnosis of SARS-CoV-2 infection.The Cochrane database of systematic reviews · 2022Pooled it
- Accuracy of novel antigen rapid diagnostics for SARS-CoV-2: A living systematic review and meta-analysis.PLoS medicine · 2021Pooled it
- Assessment of Residual-Serum SARS-CoV-2-N-Antigen Testing for Hospital Surveillance in Germany.Journal of medical virology · 2026Article
- Plasma SARS-CoV-2 nucleocapsid antigen levels are associated with lung infection and tissue-damage biomarkers.Virus research · 2025Article
- Aptamer-engaged nanotherapeutics against SARS-CoV-2.Discover nano · 2025Review
- Diagnostic Utility of SARS-CoV-2 Nucleocapsid Antigenemia: A Meta-analysis.Open forum infectious diseases · 2024Article
- SARS-CoV-2 antigenemia and RNAemia in association with disease severity in patients with COVID-19.Scientific reports · 2024Article
- Performance of Blood-Based Nucleocapsid Antigen Tests for Diagnosis of Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Infectious Viral Shedding: A Systematic Review.Open forum infectious diseases · 2023Review
- A Reagent and Virus Benchmarking Panel for a Uniform Analytical Performance Assessment of N Antigen-Based Diagnostic Tests for COVID-19.Microbiology spectrum · 2023Article
- In vitro evidence against productive SARS-CoV-2 infection of human testicular cells: Bystander effects of infection mediate testicular injury.PLoS pathogens · 2023Article
- Investigation of Blood Plasma Viral Nucleocapsid Antigen as a Marker of Active Severe Acute Respiratory Syndrome Coronavirus 2 Omicron Variant Infection.Open forum infectious diseases · 2023Article
- SARS-CoV-2 N-Antigen Quantification in Respiratory Tract, Plasma and Urine: Kinetics and Association with RT-qPCR Results.Viruses · 2023Article
- Diagnostic value and characteristic analysis of serum nucleocapsid antigen in COVID-19 patients.PeerJ · 2023Article
- Dual detection of COVID-19 antigens and antibodies using nanoscale fluorescent plasmonic substrates.Experimental biology and medicine (Maywood, N.J.) · 2022Article
- Nucleocapsid Antigenemia Is a Marker of Acute SARS-CoV-2 Infection.The Journal of infectious diseases · 2022Article
- Evaluation of Severe Acute Respiratory Syndrome Coronavirus 2 Nucleocapsid Antigen in the Blood as a Diagnostic Test for Infection and Infectious Viral Shedding.Open forum infectious diseases · 2022Article
- Review
- Clinical Added Value of SARS-CoV-2 Antigen Detection in Blood Samples.Diagnostics (Basel, Switzerland) · 2022Article
- In vitro evidence against productive SARS-CoV-2 infection of human testicular cells: Bystander effects of infection mediate testicular injury.bioRxiv : the preprint server for biology · 2022Article
- Plasma SARS-CoV-2 nucleocapsid antigen levels are associated with progression to severe disease in hospitalized COVID-19.Critical care (London, England) · 2022Observational
Corrections and comments
- Erratum issued
Authors and funding
29 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectivesMolecular assays on nasopharyngeal swabs remain the cornerstone of COVID-19 diagnostic. The high technicalities of nasopharyngeal sampling and molecular assays, as well as scarce resources of reagents, limit our testing capabilities. Several strategies failed, to date, to fully alleviate this testing process (e.g. saliva sampling or antigen testing on nasopharyngeal samples). We assessed the clinical performances of SARS-CoV-2 nucleocapsid antigen (N-antigen) ELISA detection in serum or plasma using the COVID-19 Quantigene® (AAZ, France) assay.
methodsPerformances were determined on 63 sera from 63 non-COVID patients and 227 serum samples (165 patients) from the French COVID and CoV-CONTACT cohorts with RT-PCR confirmed SARS-CoV-2 infection, including 142 serum (114 patients) obtained within 14 days after symptoms' onset.
resultsSpecificity was 98.4% (95% confidence interval [CI], 95.3 to 100). Sensitivity was 79.3% overall (180/227, 95% CI, 74.0 to 84.6) and 93.0% (132/142, 95% CI, 88.7 to 97.2) within 14 days after symptoms onset. 91 included patients had a sera and nasopharyngeal swabs collected in the same 24 hours. Among those with high nasopharyngeal viral loads, i.e. Ct value below 30 and 33, only 1/50 and 4/67 tested negative for N-antigenemia, respectively. Among those with a negative nasopharyngeal RT-PCR, 8/12 presented positive N-antigenemia; the lower respiratory tract was explored for 6 of these 8 patients, showing positive RT-PCR in 5 cases.
conclusionThis is the first evaluation of a commercially available serum N-antigen detection assay. It presents a robust specificity and sensitivity within the first 14 days after symptoms onset. This approach provides a valuable new option for COVID-19 diagnosis, only requiring a blood draw and easily scalable in all clinical laboratories.
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